The answer would be synaptic pruning.
The brain in children will have a much more synaptic connection than adults. This connection is important for learning process in the early stage of life. More synaptic connections allow multiple parts the brain areas to be connected even if there is a damage in one area.
The synapse will be cut down later in a process called synaptic pruning. Only the area that frequently used will be preserved.
Answer:
Some similarities: they both contain water: ocean in a liquid form and atmosphere as water vapor and oxygen, although oceans have relatively little oxygen (but enough for the fish to catch).
Major difference is that the main substance in the atmosphere is various gasses, while the main substance in the ocean is water in liquid form.